A group of motherboard enthusiasts working for GIGABYTE, sharing their insider knowledge and general ramblings of the motherboard business, the tech industry, latest technologies and trends, and other random odds and ends.

The overclocking crew used GIGABYTE Z170X SOC Force LN2 and X99 Champion motherboards and G.Skill Trident Z memory. The world records in particular were also powered by the new Nvidia GTX 1080 graphics cards!

Wednesday, June 1, 2016

1.SINGLE BIOS mode: make sure you turn it
ON (position 2). This switch will disable Dual bios mode in case it triggers a
bios switch or update due to OC fail.

2.This CPU_Mode switch is ONLY required
for 5960X (Haswell-E) and it is not required for Broadwell-E (6950X). We
suggest that you leave it in DEFAULT position (position 1)

3.POWER DRAW: Our testing has shown that
Broadwell-E draws less power than Haswell-E, despite the fact it has a higher
amount of cores. This is welcome news as some PSUs were having problems with
OCP shutdown as power draw exceeded the Amp draw limit on 12V rail. This may
still be happening on PSUs of lesser quality or with aggressive OCP spec. We
recommend discussing with peers what PSUs to use for extreme OC.

4.CB (Cold Bug) & CBB (Cold Boot Bug) changes: From our experience testing 6950X CPUs, we've seen very similar
behaviour with CB and CBB overall. CB is generally between -95C and -110C. CBB
is more CPU specific and can sometimes be same as CB but mostly ranges around
-90C.

Some tips: Find your CB
and CBB first and test it a few times. Once you have a rough idea, it will make
it a lot smoother to bench your CPU. Here are some post LED codes to watch out
for:

·Post Code "bF": When you
restart and you see post code "bF", switch off PSU and let all power
drain from board before switching PSU back on, start again. Most times it will
boot straight back up and you are ready to go. However, you may see post code
91!

·Post Code "91": Switch PSU
off if you see this post code, let power drain from board (you will see power
LED light turn off on board so there is no residual power in the board), switch
PSU back on and hit start and go. Sometimes you may need to go warmer than your
regular CBB (i.e from -90C to -80C) to avoid post code 91.

·Core Voltage: Air cooling 4GHz, you
are looking at around 1.2vcore. We tested up to 1.35vcore with benchmarks such
as XTU and found CPUs were mainly running below throttling temperature and
frequency of up to 4.4GHz.

LN2 cooling we find that it's best to start with 1.5v at -60C and go colder.
Most CPUs will like 1.55vcore with -80 to -110C. Some chips will scale higher
with 1.6v-1.7v but majority we tested stop scaling up to 1.6vcore. Majority of
CPUs did 5GHz, great CPUs did 5.2GHz and special chips will go beyond 5.3GHz with
Cinebench R15. This may change with new retail batches.VRIN is another voltage you need to use (up to 2V on air and generally 2.2v LN2). 2.6v can kill CPUs so be careful.PLL TRIM is the last one to look out for. Use +15. Improves OC performance and stability.

LLC (load line calibration), set to Extreme (refer to screenshot below for full settings).

·Uncore Voltage: This voltage has
changed compared to Haswell-E. There are two voltages that affect uncore/cache
frequency. One is "VRING" and other is "VccU Offset".

Air testing showed that uncore will scale to 3.75GHz
roughly using up to 1.40VRING and +0.25 VccU Offset. You don't really need high
VccU offset for air or LN2, +0.25 is generally enough for majority of CPUs.

LN2 testing showed that uncore will scale to 4.6GHz
roughly using a mix of voltage and correct temperature. In terms of voltage, we
could see uncore scaling up to 1.6VRING and we use +0.25 VccU Offset. You can
try higher voltages and see if it helps with your CPU. Temperature is very
important with uncore. You must be cold enough to boot at very high uncore
clocks (-80C or colder). We recommend booting at lower uncore and using GTL to
clock up core and uncore frequency in OS.

Post Code tips: If
you see the post code looping after restart and board suddenly shuts down, that
usually means the uncore is too high for that boot which will either need
colder temp or bios reset and reloading profile. You may see postcodes such as
"b0", "bF", "b2" but it might be others as well.

·Memory Voltage: We will specifically
refer to B-die based memory ICs here as they have shown to be best for extreme
OC. There are two different volts (VSA & memory volts) you need to use to
clock memory well as well as memory voltage training.

VSA voltage is generally recommended in +0.25 to +0.35v.

Memory voltage we generally use 1.6v for 3000MHz
12-12-12-28. For 3400MHz and higher, we use 1.7-1.75v. CPU must be cold (use
-80C or higher).

·Voltage Limits: CPUs did not really
scale past 1.7vcore. Uncore voltage did not really scale past 1.6v on most
CPUs. Memory voltage we suggest keeping below 1.8. Offset voltage and VSA are not needed any
higher than previously shown. These are extreme limits and you must find out
what your CPU and memory like. If you use too high a volts, you will probably
lose max MHz frequency. Best to find the ideal volts for your hardware!

6.Post Code LED tips: Please check point
4. & 5. for some tips. We will also provide some additional info for
various memory related post code troubleshooting below:

·Post Code "61":
Overtightening CPU pot can cause this post code. This can also be pure memory
frequency or vdimm limitation. If a RAM slot is wet, it can also show 61.

·Post Code "50": System not detecting memory correctly due to
dirt in dimm slot or not inserted properly. Tight timings limitation can also
show this code.

7.CPU temperature, paste, correct mount and stability: Make sure you have a stable mount when you are overclocking. You
will find that once you start to push high frequency and volts that your paste may
not work correctly and can become unstable and previously stable frequency.
Best way to OC is to use a staggered approach where you start with 4.5GHz
profile, 4.8, 5 , 5.2 with specific volts and temp ranges. If you crash at any
stage, you probably "lost your mount". Essentially your paste snapped
and is not conducting heat properly between CPU HS and CPU pot. One way you can
detect this is via a delta probe (keep one temperature probe on HS and second
on CPU pot). Quick way to fix this is to turn off system and cool down to -25C
and then quickly bring back temps down to cold and start. 90% if the time, you
will be able to clock high again but may not be able to get max clocks until
full paste remount (full CPU pot warm up, paste replacement etc)

11.Voltages for Uncore (make sure
CPU_Mode switch is turned to ENABLE (position 2)
In the CPU Advanced Voltages when you
have switched to the OC mode you will see some extra voltages. VL1 to VL6.

You only have to change VL4, VL5 and VL6 as below.

The voltage you have to change to get
higher uncore is mostly the VL6. Almost all the CPUs can do 1.45V, most of the
CPUs can do 1.5V but some CPUs can do even higher Voltage. There are few CPUs
that boot with lower than 1.45V though. If the CPU can do high VL6 then
probably it can do and high Uncore but not all the times. It depends on the
CPU. In the OS through GTL all you have to do is to raise the VRING to
1.45V-1.5V in able to get high Uncore.

12.RTLs.
You can change the RTLs but not manually only changing the IOLs manually.
IOLs to 1 will bring the RTLs all the way down to what the board is capable of
until now.
You need to change the IOLs at every channel. Set the option at manual mode and
change the primary and secondary timings
only for channel A and then change the IOLs to each channel manually.

13.Use both 8pin and 4pin cables
for CPU Power otherwise with heavy load the system maybe will be shutting down.

14.You don’t need extremely high
VSA and VDIMM. VSA between +0.25-0.35V should be enough to drive the mems high.
+0.25-+0.3V should max your mems on most cases. VDIMM 1.55-1.65V is ok. I was
able to do even C11 with 1.6V.

15.Few times you will see codes
like 72, 74, 50, 51, 60, 8A. Try to press the reset button few times. There’re
times that doing it it passes the training. Especially when you change the RTLs
and you get 8A try it for sure. It doesn’t happen on latest bios so often.https://www.dropbox.com/s/g46ggra2mtkvv4z/F4f.rar?dl=0

Highest bootable VL6 cannot be overridden through software. Same value that
your CPU won’t boot from bios if you set it through software it will shut down.

17.Please be careful! The VLs can
affect your CPU cold bug so make sure that when you change you don’t hit the
cold bug earlier than before. If you have this problem try higher or lower VL3
(usually higher helps). If VL3 doesn’t fix your problem then try the same for VL6.
Also, different bclk affects the cold bug too, so try this as well. Almost all
the CPUs are ok with 127.5 bclk and PCI3.

18.Make sure that you’re using
proper insulation around the memories area and also put some paper towel around
the PCH cooler. The way that worked best for us was a layer of plastidip, then
a layer of Vaseline and paper towel.

19.Always save a profile before
you save and exit cause most of the times the only way to go back is the CMOS
button.

20.For memory voltage we used up
to 1.9V on single sided dimms on LN2 without a problem. But it doesn’t mean
that all the dimms can handle it so be careful in case you don’t want to
degrade or kill your memories. Dino was benching with 1.8V without any issue.